Is there a build thread for this guys motor, like to do some studying. I'm building a 56 pickup with a stock 351w.

 

I bookmarked this link, thanks.

 

Here it is: http://www.theturboforums.com/threads/358359-1980-Notch-351-S480-8-11-13-9-73-140

He has the same philosophy I do...keep it safe (low timing) and the stock parts will live.

 

Thanks, looks like I have some reading t do tonight.

 

Post 17 on FTE:

JP3: Initally was going front mount, just a bit shy on room hear and there for the 2.5 pipe without making it look like a cork screw. Then factor in nose heavy truck, with a 117 w.b., I figured 50# behind the rear axle would do a whole lot more than in front of the front axle taking weight off the rear tires. Having a truck that hooks on the street is priority for me, mostly for tuning purposes. Then I also feel confident it will hook at the track. I literally have a semi trailer full of 460's and 429's, but didn't want 200 extra pounds on the nose and need slicks to make it hook.

The rear mount has many benefits such as rear/front weight bias, cooler exhaust temps hitting the turbo, long boost pipe provides some intercooling, long feed and return oil lines run cooler, and a super short 4" down pipe makes more power, spools quicker, and puts the noise in the back.

Dale

 

It spooled pretty darn good with the t72. The 3100 stall puts it in range right now. When I had a 2100 stall, the t72 started boosting at 2800 and made full boost around 3200-3300. So you see at 3100 plenty of exhaust volume, just put the hammer down and load the turbo. There is a small delay at 2400 rpm as the long pipe starts to scavenge. You can see it on the tach in the walk around vid. It "raps" at that rpm and sounds neat.

The Gt45 with the bigger exhaust wheel and housing starts to boost around 3100, and lites at 3800. The converter goes straight to 5000 once lit, so I don't really know where full boost is. I'm guessing around 4500. This much spread clearly indicates too much turbine exhaust flow for 300 cubes. This is why I will need nitrous when I put the tight Pro Edge converter back in. Nitrous pumps up the exhaust volume as more cubes would. I will use as little nitrous as possible, so I don't have to go with a bigger wastegate.

The Gt45 won't do much from a stop sign, but if i'm rolling 3500 in any gear and nail it, hang on! It's cubes vs rpm vs turbine size. Front vs rear is negligible. Rear mount does require more warm up time. Rear mount may even be better in the upper rpms, as there is more cushion for the exhaust pulses to escape the cylinder...don't know.

We put the exact same t72 in the front with a spool valve on the 3.8, with a 2900 stall, it takes around 7 seconds to spool it. That's lag! Rolling down the road at 3500, spools right now. Cubes vs rpm vs turbine size (and pipe sizing and camshaft and head flow) will determine whether a turbo is laggy or not.

The fastest spooling setup(front mount) I have seen is a 414 stroker windsor with big roller cam and Vic Jr. heads. Should have made 500hp n.a. It had 1 ebay gt45 on it, as fast as the vacuum needle dropped, the boost came up!(8psi) Made around 500 to the wheels and 600 tq. It is fun to drive but choked out around 4500 rpm on the dyno graph. It's a balancing act. 2 gt45's would have probably made a 1000hp with little lag. He put the turbo kit on just to see what it would do.

If I was to guess, I would say you could be looking at a half second delay from front to rear mount, but that is just going by the o2 sensor. It seems to have a slight delay mounted in the down pipe way out back. I want a big turbine to make more power per lb. of boost, as aftermarket heads for the 300 are limited lol!

 

I had one in my '87. The ex told me that I could put what I wanted into it once it let go. I killed the truck before that 4.9!

 

Pulls strong to about 5100 rpm.

 

I'll be pulling the engine soon to freshen, the converter in there now is sold. Yes the converter window is small, going up to 3000 flash with the pro edge converter and about 4500 true would be perfect. I am working with Andre at Edge converters to see what he can do for stalls at 800 ft lbs tq. My pro edge from him flash stalled to 2100 because when I ordered it, it was built for a turbo 460, my original plan. When boosted at about 3200 when the t72 lit, it only pushed up 500 rpm, nice and tight, but the 2100 flash just doesn't work good with my combo. I want at least a 3000 flash to be safe with n2o. The pro edge has proven to be much tighter than the current converter.

I am using Shaeffers ss315: http://www.schaefferoil.com/simplex-transmission-fluid.html Very happy with it, and runs cooler that Mobil 424. I get it locally for $5/quart. Atf doesn't last long in my truck!

 

Been thinking about a custom cam I've been working on for my truck, but I feel 5200-5300 is enough with the 4" stroke. Piston speed is equivalent to a 351 turning 6000 rpm or a 302 turning 6900 rpm.

 

Finally filled the last vacancy in the bed with purple goodness!

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Pretty neat cargo.